1. Field of the Invention
The present invention relates to a method of horticultural protection of plant growths during the maturation thereof whereby the volume exchange of oxygen, carbon dioxide, and moisture between the plant and ambient environment is controlled in accordance with the demands thereof by the plant growth during the maturation period. Also, the present invention relates to the article to affect this horticultural protection.
2. Descrption of the Prior Art
The prior art recognizes both the need and desirability to afford horticultural protection for plant growth during the maturation thereof. Various forms of plastic webs or other agronomic mulch sheets have been fashioned to aid in the tillage of plants, crops and the like.
The application of such webs as a means for providing climatic control about a local area surrounding the plants under cultivation has been known for many years. For example, U.S. Pat. No. 3,580,196 relates to an agronomic mulch sheet possessing a plurality of openings in a row therein. Each of these openings is provided with a slit or other means to allow an expansion of the opening upon subsequent growth of the plant therethrough. Such an agronomic mulch web is capable of retaining the soil surrounding the plant in place and confines plant growth to a uniform row defined by the openings of the web. As growth proceeds, the mulch will lie adjacent the surface of the ground. Once the plants have gained a substantial size, the plastic mulch sheet may be removed directly over the plants by virtue of the openings capable of expansion.
French Pat. Nos. 1,589,499 and 2,056,070 and German Offelegungsschrift No. 2,348,512 all relate to conceptually similar agronomic mulch sheets suitable for limited horticultural protection.
By and large, the prior art mulch webs are deficient in one or more aspects. Typically, the perforations formed in the web are tightly closed when the sheet is applied to the soil. This results in an enrichment of the environment between the web and the soil with carbon dioxide released by ground. Such enrichment of carbon dioxide is known to be prejudicial to the development of young plants. Even in the event that the perforations are not entirely sealed, the relative distance between adjacent holes is typically substantial, thus resulting in gradients in carbon dioxide concentration which, too, is undesirable. Also, until plant growth has reached substantial proportion, these webs minimize the free exchange of moisture which may be deleterious to healthy establishment of plants during the incipient stages of growth. Furthermore, such tightly closed mulch sheets do not allow convenient irrigation of the plants. Most of the irrigation water flows away, whereas the water which passes through the perforations erodes the soil surrounding the plants, even though the quantity of water is not sufficient for the plants.
Moreover, the minimal amount of protection afforded the plant substantially ceases once the stem or foliage protrudes above the level of the web. The mulch sheet must then, generally, be removed or possibly contribute to a restriction of healthy maturation. The removal of the web after the protrusion of the foliage can also damage the tender shoots as they are pulled back through the openings.
Accordingly, a need exists to provide horticultural protection for flora both during the pre-emergence and subsequent maturation thereof. Moreover, the need exists to provide such protection which will minimize soil erosion during pre-emergent stages but which will allow sufficient irrigation of the plants. Additionally, the need exists to provide such horticultural protection which is free from characteristics contributing to either an excessive accumulation of carbon dioxide, as well as undesirable gradients thereof, beneath the horticultural web.